Electrode for arc-lamps.



E. R.- BERRY & E. J. GUAY.

V ELECTRODE FOR ARQ LAMPS.

APPLIbATION FILED JULY 9, 1909.

Pate'qted Nov. 1, 1910.

Nltnesses. 7 59M 5. Aim. %u.

UNITED STATES PATENT oEEIoE.

EDWARD R. BERRY AND EMILE'J. GUAY. OF LYNN, MASSACHUSETTS, ASSIGNORS TGENERAL ELECTRIC COMPANY. A CORPORATION OF NEW YORK.

ELECTRODE FOR ARC-LAMPS.

Specification of Letters latent.

Application filed July 9, 1909. Serial No. 506.747.

Patented Nov. 1, 1910.

Itain new and usetul Tmprovements in Electrodes made of an irontubecontaining a considerable, percentage of titanium earbid i trodes torAre-Lamps, of which the following is a specification. 1

()ur invention has reference to improvements in electrodes for are lampsin which titaniumcompound is used. either alone or as one ottheingredients of a filling for an electrode tube, the. object of theinvention beingto prevent the sticking to the glass globe of the hotparticles thrown otl by the electrode. [thas been found thatthe utilityof elec is largely impaired by the fact thatin its use fused particlesare thrown off from the arcing end of the electrode and are projected 1against the inclosing globe, which, being made of glass. is fusedsuperficially-at the points where the hot particles come in contact withthe same, and these particles then stick to the glass. By the continueduse of the electrode this spitting and the adherence of the projectedparticles to the glass gradually impairs'the transparency of the globe,so that after a comparatively short time the globe intercepts so muchlight that it has to be renewed. H has been found thatthe globe cannotbe cleansed by any mechani *al means nor elliciently by any chemicalmeans, and theobject of our invention is to avoid the adherence of theprojected particles of hottitanium carbid or titanium compounds mixedwith the fused iron shell to the glass. \Ve have discovered that when inplace of the iron tube an aluminium tube is used the aluminium fuses atthe arcing end together with the titanium 'carbid or other titaniumcompound to a mass that does not adhere to 5 tube.

; glass when thrown oil from the arcing end and projected on to theglobe.

Our invention, therefore, consists in a titanium carbld or tnanlumcompound electhe titanium compound compactedtherein. In the accompanyingdrawing, which ftrode made of a tube of aluminium having terms a part ofthis specification. we have illustrated. in longitudinal section, anelec-- trode made in accordance with our invention.

The electrode is composed of analuminium shell or'tube 1, closed at thelower end by a plug of any suitable material, and having titanium,carbid, or a mixture of titanium earbid with other materials, or othertitanium compounds, in a finely divided state, as indicated at 3. packedin the is ot no particular consequence, and for practical purposes thetube will be made just strong enough to give the requisite rigidity tothe electrode, and the filling of the tube may be either titanium carbidalone or titanium carbid mixed with other substances, or any othertitanium compound, so long as the titanium is present in sufficientquantity The thickness of the walls of thetube to give to the air thepeculiar characteristic EDWARD R. BERRY EMILE J. GUAY.

lVit-nesses JOHN A. MCMANUS, Jr., RICHARD G. PovEY.

